Antistatic fuel composition

ABSTRACT

Antistatic fuel composition comprising a mixture of hydrocarbons in the gasoline, kerosene and/or furnace oil boiling ranges and a minor amount of a reaction product of an aliphatic monoamine having the formula RNH2 in which R is an aliphatic radical having from eight to 20 carbon atoms and either a fluorinated polystyrene having the empirical formula: (C16H3F25)x in which x is an average integer between 3 to 5, or a fluorinated polypropylene having the empirical formula: (C3HF5)x in which x has a value from 20 to 40, and a method for preparing the above-noted aliphatic monoamine derivatives.

United States Patent Bialy et al.

[ 51 Mar. 28, 1972 [s41 ANTI-STATIC FUEL COMPQSITIQN [72] Inventors: Jerzy J. Bialy, Lagrangeville; William R.

Siegart, Poughkeepsie, both of N.Y.; William D. Blackley, Lake Elmo, Minn.; Harry Chaietz, Poughkeepsie, N.Y.

[52] U.S. Cl ..44/62, 44/72 [51] Int. Cl ..Cl0I1/20, ClOl H22 [58] Field of Search ..44/72, 62, DIG. 2; 260/935 A,

[56] Relerences Cited UNITED STATES PATENTS 3,003,858 10/1961 Andressetal. ..44/62 3,461,162 8/1969 Koshar et al. ..44/72 X Primary Examiner-Daniel E. Wyman Assistant Examiner-W. J. Shine Attorney-Thomas H. Whaley and Carl G. Ries [57] ABSTRACT Antistatic fuel composition comprising a mixture of hydrocarbons in the gasoline, kerosene and/or furnace oil boiling ranges and a minor amount of a reaction product of an aliphatic monoamine having the formula RNl-l in which R is an aliphatic radical having from eight to 20 carbon atoms and either a fluorinated polystyrene having the empirical formula:

(C HJ in which x is an average integer between 3 to 5, or a fluorinated polypropylene having the empirical formula:

(C l-IE in which at has a value from 20 to 40, and a method for preparing the above-noted aliphatic monoamine derivatives.

1 1 Claims, No Drawings BACKGROUND OF THE INVENTION 1. Field of Invention Distillate hydrocarbon fractions, such as gasoline, kerosene, diesel oil and furnace oil, are inflammable to highly inflammable materials and must be protected from accidental ignition. Another property of these fuels is that they are relatively nonconductive with respect to electricity.

Very large volumes of liquid hydrocarbon fuels, i.e. gasoline, kerosene, diesel oil and furnace oil, are transferred daily through pipelines, hoses and like equipment. Because the volumes are so great, many of these operations are conducted using high velocity pumping means as in the loading of ships, storage tanks and aircraft. Because of the non-conductive nature of these normally liquid hydrocarbons, static electricity builds up and accumulates in the fuel during the high speed pumping operations. This static electricity build-up is inherently dangerous and is known to have caused disastrous fires and explosions in the past.

The present invention is directed to a novel fuel composition having improved electrical conductivity and, therefore, anti-static in nature. This invention is also directed to a novel method for preparing the anti-static additive.

2. Description of the Prior Art Fluorinated hydrocarbons including fluorinated polystyrene and fluorinated polyolefins are well known in the art. F luorinated polystyrene having the empirical formula (C H F ,,)x where x is 3 to 5 and a method for preparing these compounds is disclosed in U.S. Pat. No. 3,380,983. According to this patent, a fluorinated polystyrene is prepared by contacting a polystyrene having a molecular weight between about l0,000 and 500,000 with gaseous fluorine in the presence of an alkali metal fluoride catalyst at a temperature between about and l05 C. The resulting products have the empirical formula (C, H F )x where x is 3 to 5 and having a melting point of 85 to 90 C.

A specific fluorinated styrene disclosed in the patent (Example II) is represented by the empirical formula:

has a molecular weight of 2,590 and a melting point of 85-90 C. This fluorinated polystyrene comprises a mixture of telomeric compounds of varying chain length having an average of 3-87 repeating units where each repeating C H F unit in the chain consists of two chemically fluorinated cyclohexane analogs of styrene.

U.S. Pat. No. 3,0l3,868 discloses a liquid hydrocarbon composition having increased electrical conductivity due to the incorporation of a conductive additive to the liquid consisting of a salt of a metal having an atomic number from 22 through 28 and a high molecular weight aromatic, carboxylic or sulfuric acid. Specific conductivity additives are chromic diisopropyl salicylate, chromic dioctyl sulfosuccinate and vanadium petroleum sulfonate. This reference also discloses that the effectiveness of the conductivity additives can be improved by the further addition of salts of nitrogen-containing copolymers.

SUMMARY OF THE INVENTION The anti-static fuel composition of the invention comprises a mixture of hydrocarbons in the gasoline, kerosene, diesel oil and furnace oil boiling ranges containing a minor amount of an aliphatic monoamine reaction product of either a fluorinated polystyrene or a fluorinated polypropylene. More specifically, the fuel composition, which will generally boil from about 90 to about 750 F., contains an effective antistatic amount of an aliphatic monoamine reaction product of an aliphatic monoamine having the formula RNH in which R is an aliphatic radical having from eight to 20 carbon atoms and either a fluorinated polystyrene represented by the empirical formula:

( ra aFu) in which x is an average integer of between 3 to 5, or a fluorinated polypropylene represented by the empirical formula:

in which x has a value from 20 to 40. The method for preparing the aliphatic monoamine reaction product involves the reaction of the corresponding fluorinated polymer with a primary aliphatic monoamine at a temperature in the range of 50 to 200 C. and in the presence of a tertiary amine catalyst, such as a trialkylamine having the formula R N in which R is the same or different aliphatic radicals having from one to 30 carbon atoms. The preparation of the fluorinated polystyrene component of the reaction product of the invention having the empirical formula C,,H,F,, x in which x is an average integer between 3 to 5 is fully described in U.S. Pat. No. 3,380,983 referred to above. I The fluorinated polypropylene component of the reaction product of the invention was prepared in essentially the same process used for the fluorinated polystyrene. In general, a

solid polypropylene having a specific gravity from about 0.880 to 0.908 is deposited on sodium floride and dried and ground in a mill to pass through a 1 mm. screen. The treated polypropylene is charged to a reactor and the reaction mixture chilled. Fluorine diluted with nitrogen is added to the stirred reaction mixture until fluorine is detected coming from the reactor. The reaction is then continued at room temperature until fluorine is detected coming from the reactor at which time the reactor is heated to an elevated temperature about C. and the reaction continued until fluorine issues from the reactor. The reactor is flushed with nitrogen and the fluorinated polypropylene recovered by solvent extraction as disclosed in the above-noted patent. The fluorinated polypropylene product has the empirical formula (C l-W in which at has a value from about 20 to 40 preferably from 23 to 35.

The following example illustrates the preparation of the fluorinated polypropylene of the invention:

EXAMPLE I Thirty grams of polypropylene having a specific gravity of 0.905 and a crystalline melting point of 333 F. was dissolved in 500 ml. of boiling cumene and 265 grams of sodium fluoride added to the solution. The suspension was cooled to room temperature, filtered, washed with ether, and dried. The solids were ground in a mill to pass through a 1 mm. screen, again washed with ether, dried, and charged to a reactor. Fluorine diluted with nitrogen was passed into the reactor, which was cooled in an ice bath, until a positive fluorine test was obtained at the exit end of the reactor. The fluorination was then continued with the reactor at room temperature until a positive fluorine test was obtained at the reactor exit. Heat was then applied and the reaction continued. The fluorination was terminated when the reactor skin temperature was 85 C. and a positive fluorine test was obtained at the reactor exit. The reactor was flushed with nitrogen and the solids removed from the reactor and extracted twice with 800 ml. portions Freon l 13. The Freon was removed under reduced pressure to yield 75.5 grams of fluorinated polypropylene having a molecular weight of about 4612 and the following analysis:

Carbon, wt percent 25.2 Hydrogen, wt percent 0.4 Fluorine, wt percent 74.1

The fluorinated polystyrene and fluorinated polypropylene noted above are reacted with an aliphatic monoamine to form the corresponding amine reaction product which provides anti-static properties in the distillate hydrocarbon fuel oil composition. In general, this method involves the reaction of a fluorinated polymer containing at least one unsubstituted hydrogen atom with a primary aliphatic monoamine having the formula:

. preferably at a temperature from 80 to 150 C.

Examples of primary and secondary aliphatic monoamines which can be employed in this reaction include octylamine, decylamine, dodecylamine, tetradecylamine, hexadecylamine and octadecylamine; dodecylamin'e and octadecylamine being particularly preferred.

The tertiary amine catalysts which can be employed in the reaction include trimethylamine, triethylamine, tripropylamine, tributylamine, triamylamine, trioctylamine, pyridine, pyrimidine, pyrazine and the like. In general, the catalyst can be represented by the formula R N where R is a hydrocarbon radical, preferably an alkyl radical having from one to 30 carbon atoms. It is also understood that the Rs can be connected to form a cyclic tertiary amine compound.

The reaction is conducted using approximately one equivalent of the aliphatic monoamine and two equivalents of the tertiary amine catalyst for each hydrogen atom in the fluorinated polymer.

The following examples illustrate the preparation of the aliphatic monoamine-fluorinated polymer reaction products of this invention.

EXAMPLE II PREPARATION OF THE DODECYLAMINE DERIVATIVE OF FLUORINATED POLYSTYRENE methanol-water mixture. The pentane was removed from the solution under vacuum and 78.0 grams of product was isolated. Infrared analysis of the product confirmed that it was an amine reaction product of the fluorinated polystyrene. The product was a black viscous liquid having the following elemental analysis:

EXAMPLE III OCTODECYLAMINE DERIVATIVE OF FLUORINATED POLYPROPYLENE Into a reaction flask was charged 102. grams of octadecylamine, 80.0 grams triethylamine, 200 cc. of 1,4-dioxane and 50.0 grams of the fluorinated polypropylene of Example I. This reaction mixture was stirred together at reflux for 16 hours and cooled to room temperature. Two Hundred cc. of pentane was added and the mixture filtered. The solids were extracted with an additional 500 cc. of pentane and the filtrates were combined. The solvent was removed under water asperator vacuum and the product extracted with two 300 ml. portions of pentane. The pentane was removed under vacuum and the resulting solid product extracted with two 500 ml. portions of ethyl alcohol and dried. A yield of 83.1 grams of a black solid melting at 38C. was obtained. Infrared analysis taken in Nujol and fluorolube mulls confirmed that the product was the amine derivative of fluorinated polypropylene and that olefin was present in the chemical structure. The product analyzed as follows:

% Carbon 64.9 check 65.1

% Hydrogen 9.0 check 9.]

% Fluorine 20.5 check 20.9

Molecular weight 2,430

EXAMPLE IV OCTADECYLAMINE DERIVATIVE OF FLUORINATED POLYSTYRENE Into a reaction flask was charged 50.0 grams of triethylamine, 50.3 grams of fluorinated polystyrene having tllg fQ 1 Q lHa E)3.q 61.7 grarn s of octadecylamine and 200 cc. of 1,4-dioxane. These materials we re refltEted with stirring for 16 hours. The reaction product was removed from the flask, 300 cc. of benzene added, and the mixture filtered. The solvent was removed from the filtrate under vacuum, 500 ml. of pentane added to the residue, and the mixture filtered. The pentane was removed from the filtrate under vacuum and the residue was extracted first with two 250 ml. portions of methyl alcohol and then with two 500 cc. portions of methyl alcohol and dried. A yield of 71 grams of a tacky,

gum-like solid with a melting point of 35-40 C. was ob- EXAMPLE V DODECYLAMINE DERIVATIVE OF FLUORINATED POLYPROPYLENE Into a reaction flask was charged 70.0. grams of dodecylamine, 75.0 grams triethylamine, 200 cc. of 1,4-dioxane and 45.0 grams of the fluorinated polypropylene of Example I. The reaction mixture was stirred at reflux for 16 hours, then cooled and filtered. The solvent was removed under vacuum, and the resulting product extracted with 200 ml. portions of pentane. The pentane removed under vacuum and a viscous black residue extracted with two 200 ml. portions of 95 percent ethyl alcohol. The insoluble material remaining was dried to yield 59.7 grams of a black, viscous liquid. Infrared analysis of the material showed it to be an amine derivative of the fluorocarbon with strong olefin absorption. Elewithin the noted boiling range. Specific fractions which can he employed for preparing the fuel compositions of the invention include gasoline boiling from about to 425 F., kerosene boiling from about 300 to 525 F gas oil and diesel oils boiling from about 390 to 750 F. and furnace oils boiling from about 300 to 750 F. or higher.

The anti-static fuel composition of the invention is prepared.

by blending a minor anti-static effectiveamount of the abovedescribed additives to the base fuel.,.ln general, the anti-static additive is employed at a very low concentration ranging from about 0.01 to 1000 p.p.m. (weight parts per million parts of fuel). A preferred concentration range is from about 0.05 to 25 p.p.m., with the most preferred range being from 0.1 to 10 p.p.m. I

The electrical conductivity or anti-static properties of the base fuel and of the fuel compositions of the invention were determined in a Resistivity Test according to ASTM Method Dl169-64. In this test, the resistivity of fuel is tested by the electrical conductivity found between two electrodes immersed in the fuel samples.

The base fuel employed in these tests was a typical turbine or jet fuel having the following inspection values:

The electrical conductivity of the fuel compositions expressed in Resistance in ohm-cm. is set forth in the following table. The additive concentration employed was 1 ppm.

TABLE I Resistance Run Additive ohm-em.

l None-base fuel 2.662Xl" 2 Example ll 83x10" 3 Example lll 145x10" 4 Example lV BXIO" 5 Example V 8X10" 6 Commercial additive IJOXIO" It is evident from the data that the anti-static fuel composition of the invention is highly effective for improving the electrical conductivity of the hydrocarbon base fuel. These fuel compositions are superior in their anti-static properties to a fuel composition containing a commercial anti-static additive at the same concentraction level.

Obviously, many modifications and variations of the invention, as hereinbefore set forth, may be made without departing from the spirit and scope thereof, and therefore, only such limitations should be imposed as are indicated in the appended claims We claim:

1. A fuel composition comprising a mixture of liquid hydrocarbons boiling from about 90 to 750 F. containing a minor antistatic effective amount of a reaction product of an amine and a fluorinated polymer having at least one unsubstituted hydrogen atom from the group consisting of fluorinated polystyrene and fluorinated polypropylene, said aliphatic monoamine having the formula:

RNH,

in which R is a radical having from eight to 20 carbon atoms, said reaction being conducted between at least one unsubstituted hydrogen atom in said fluorinated polymer and said aliphatic monoamine in the presence of two equivalents of tertiary amine catalyst for each hydrogen reacted in said fluorinated polymer, said tertiary amine being represented by the formula:

wherein R is a hydrocarbon radical having from one to 30 carbon atoms, said reaction being effected at a temperature from about 50 to 200 C.

2. A fuel composition according to claim 1 in which the hydrocarbons are in the gasoline or kerosene boiling ranges or mixtures thereof.

3. A fuel composition according to claim 1 in which the mixture of hydrocarbons are in the furnace oil boiling range.

4. A fuel composition according to claim 1 containing from about 0.01 to 1000 weight parts per million parts of said reaction product of said amine and said fluorinated polymer;

5. A fuel composition according to claim 1 in which said fluorinated polystyrene has the empirical formula:

where x is an average integer of between 3 to 5, and said fluorinated polypropylene has the formula:

where x has a value from 20 to 40.

6. A fuel composition according to claim 5 in which said fluorinated polystyrene has the formula:

7. A fuel composition according to claim 5 in which said amine is dodecylamine.

8. A fuel composition according to claim 5 in which amine is octadecylamine.

9. A fuel composition according to claim 5 in which said fluorinated polypropylene has the empirical formula:

in which .1: has a value from 23 to 35.

10. A fuel composition according to claim 9 in which amine is dodecylamine.

11. A fuel composition according to claim 9 in which said amine is octadecylamine. 

2. A fuel composition according to claim 1 in which the hydrocarbons are in the gasoline or kerosene boiling ranges or mixtures thereof.
 3. A fuel composition according to claim 1 in which the mixture of hydrocarbons are in the furnace oil boiling range.
 4. A fuel composition according to claim 1 containing from about 0.01 to 1000 weight parts per million parts of said reaction product of said amine and said fluorinated polymer.
 5. A fuel composition according to claim 1 in which said fluorinated polystyrene has the empirical formula: (C16H3F25)x where x is an average integer of between 3 to 5, and said fluorinated polypropylene has the formula: (C3HF5)x where x has a value from 20 to
 40. 6. A fuel composition according to claim 5 in which said fluorinated polystyrene has the formula: (C16H3F25)3 87
 7. A fuel composition according to claim 5 in which said amine is dodecylamine.
 8. A fuel composition according to claim 5 in which amine is octadecylamine.
 9. A fuel composition according to claim 5 in which said fluorinated polypropylene has the empirical formula: (C3HF5)x in which x has a value from 23 to
 35. 10. A fuel composition according to claim 9 in which amine is dodecylamine.
 11. A fuel composition according to claim 9 in which said amine is octadecylamine. 